Remove VectorisedView everywhere.

PiperOrigin-RevId: 453471156

.buildkite/pipeline.yaml

@@ -28,7 +28,6 @@ _templates:
       PACKAGES: >
         ./pkg/tcpip
         ./pkg/tcpip/adapters/gonet
-        ./pkg/tcpip/buffer
         ./pkg/tcpip/header
         ./pkg/tcpip/link/channel
         ./pkg/tcpip/network/ipv4
@@ -37,6 +36,7 @@ _templates:
         ./pkg/tcpip/transport/icmp
         ./pkg/tcpip/transport/tcp
         ./pkg/tcpip/transport/udp
+        ./pkg/buffer
         ./pkg/waiter
 env:
   # Force a clean checkout every time to avoid reuse of files between runs.

pkg/buffer/buffer.go

@@ -18,6 +18,8 @@
 // well as the ability to grow via either prepend or append, as well as shrink.
 package buffer
 
+import "bytes"
+
 // buffer encapsulates a queueable byte buffer.
 //
 // +stateify savable
@@ -103,3 +105,10 @@ func (b *buffer) WriteMove(n int) {
 func (b *buffer) WriteSlice() []byte {
 	return b.data[b.write:]
 }
+
+// Reader returns a bytes.Reader for v.
+func (b *buffer) Reader() bytes.Reader {
+	var r bytes.Reader
+	r.Reset(b.ReadSlice())
+	return r
+}

pkg/buffer/view.go

@@ -15,6 +15,7 @@
 package buffer
 
 import (
+	"bytes"
 	"fmt"
 	"io"
 )
@@ -611,3 +612,12 @@ func (x Range) Len() int {
 	}
 	return l
 }
+
+// Readers returns a bytes.Reader for each of bufs's underlying buffers.
+func (v *View) Readers() []bytes.Reader {
+	readers := make([]bytes.Reader, 0, v.data.Len())
+	for buf := v.data.Front(); buf != nil; buf = buf.Next() {
+		readers = append(readers, buf.Reader())
+	}
+	return readers
+}

pkg/sentry/mm/BUILD

@@ -194,7 +194,6 @@ go_library(
         "//pkg/sentry/usage",
         "//pkg/sync",
         "//pkg/sync/locking",
-        "//pkg/tcpip/buffer",
         "//pkg/usermem",
     ],
 )

pkg/sentry/socket/unix/transport/BUILD

@@ -94,6 +94,7 @@ go_library(
     deps = [
         "//pkg/abi/linux",
         "//pkg/atomicbitops",
+        "//pkg/buffer",
         "//pkg/context",
         "//pkg/errors/linuxerr",
         "//pkg/fdnotifier",
@@ -109,7 +110,6 @@ go_library(
         "//pkg/sync/locking",
         "//pkg/syserr",
         "//pkg/tcpip",
-        "//pkg/tcpip/buffer",
         "//pkg/unet",
         "//pkg/waiter",
         "@org_golang_x_sys//unix:go_default_library",

pkg/sentry/socket/unix/transport/queue.go

@@ -18,7 +18,6 @@ import (
 	"gvisor.dev/gvisor/pkg/context"
 	"gvisor.dev/gvisor/pkg/syserr"
 	"gvisor.dev/gvisor/pkg/tcpip"
-	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 	"gvisor.dev/gvisor/pkg/waiter"
 )
 
@@ -167,7 +166,7 @@ func (q *queue) Enqueue(ctx context.Context, data [][]byte, c ControlMessages, f
 	notify = q.dataList.Front() == nil
 	q.used += l
 	q.dataList.PushBack(&message{
-		Data:    buffer.View(v),
+		Data:    v,
 		Control: c,
 		Address: from,
 	})

pkg/sentry/socket/unix/transport/unix.go

@@ -22,7 +22,6 @@ import (
 	"gvisor.dev/gvisor/pkg/log"
 	"gvisor.dev/gvisor/pkg/syserr"
 	"gvisor.dev/gvisor/pkg/tcpip"
-	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 	"gvisor.dev/gvisor/pkg/waiter"
 )
 
@@ -282,7 +281,7 @@ type message struct {
 	messageEntry
 
 	// Data is the Message payload.
-	Data buffer.View
+	Data []byte
 
 	// Control is auxiliary control message data that goes along with the
 	// data.
@@ -314,7 +313,7 @@ func (m *message) Peek() *message {
 //
 // Preconditions: n <= m.Length().
 func (m *message) Truncate(n int64) {
-	m.Data.CapLength(int(n))
+	m.Data = m.Data[:n]
 }
 
 // A Receiver can be used to receive Messages.

pkg/tcpip/BUILD

@@ -32,7 +32,6 @@ go_library(
     deps = [
         "//pkg/atomicbitops",
         "//pkg/sync",
-        "//pkg/tcpip/buffer",
         "//pkg/waiter",
     ],
 )

pkg/tcpip/adapters/gonet/BUILD

@@ -9,7 +9,6 @@ go_library(
     deps = [
         "//pkg/sync",
         "//pkg/tcpip",
-        "//pkg/tcpip/buffer",
         "//pkg/tcpip/stack",
         "//pkg/tcpip/transport/tcp",
         "//pkg/tcpip/transport/udp",

pkg/tcpip/adapters/gonet/gonet.go

@@ -26,7 +26,6 @@ import (
 
 	"gvisor.dev/gvisor/pkg/sync"
 	"gvisor.dev/gvisor/pkg/tcpip"
-	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip/stack"
 	"gvisor.dev/gvisor/pkg/tcpip/transport/tcp"
 	"gvisor.dev/gvisor/pkg/tcpip/transport/udp"
@@ -240,7 +239,7 @@ type TCPConn struct {
 
 	// read contains bytes that have been read from the endpoint,
 	// but haven't yet been returned.
-	read buffer.View
+	read []byte
 }
 
 // NewTCPConn creates a new TCPConn.

pkg/tcpip/buffer/BUILD

@@ -1,24 +0,0 @@
-load("//tools:defs.bzl", "go_library", "go_test")
-
-package(licenses = ["notice"])
-
-go_library(
-    name = "buffer",
-    srcs = [
-        "view.go",
-        "view_unsafe.go",
-    ],
-    visibility = ["//visibility:public"],
-)
-
-go_test(
-    name = "buffer_x_test",
-    size = "small",
-    srcs = [
-        "view_test.go",
-    ],
-    deps = [
-        ":buffer",
-        "//pkg/tcpip",
-    ],
-)

pkg/tcpip/buffer/view.go

@@ -1,315 +0,0 @@
-// Copyright 2018 The gVisor Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// Package buffer provides the implementation of a buffer view.
-package buffer
-
-import (
-	"bytes"
-	"fmt"
-	"io"
-)
-
-// View is a slice of a buffer, with convenience methods.
-type View []byte
-
-// NewView allocates a new buffer and returns an initialized view that covers
-// the whole buffer.
-func NewView(size int) View {
-	return make(View, size)
-}
-
-// NewViewFromBytes allocates a new buffer and copies in the given bytes.
-func NewViewFromBytes(b []byte) View {
-	return append(View(nil), b...)
-}
-
-// TrimFront removes the first "count" bytes from the visible section of the
-// buffer.
-func (v *View) TrimFront(count int) {
-	*v = (*v)[count:]
-}
-
-// CapLength irreversibly reduces the length of the visible section of the
-// buffer to the value specified.
-func (v *View) CapLength(length int) {
-	// We also set the slice cap because if we don't, one would be able to
-	// expand the view back to include the region just excluded. We want to
-	// prevent that to avoid potential data leak if we have uninitialized
-	// data in excluded region.
-	*v = (*v)[:length:length]
-}
-
-// Reader returns a bytes.Reader for v.
-func (v *View) Reader() bytes.Reader {
-	var r bytes.Reader
-	r.Reset(*v)
-	return r
-}
-
-// ToVectorisedView returns a VectorisedView containing the receiver.
-func (v View) ToVectorisedView() VectorisedView {
-	if len(v) == 0 {
-		return VectorisedView{}
-	}
-	return NewVectorisedView(len(v), []View{v})
-}
-
-// IsEmpty returns whether v is of length zero.
-func (v View) IsEmpty() bool {
-	return len(v) == 0
-}
-
-// Size returns the length of v.
-func (v View) Size() int {
-	return len(v)
-}
-
-// VectorisedView is a vectorised version of View using non contiguous memory.
-// It supports all the convenience methods supported by View.
-//
-// +stateify savable
-type VectorisedView struct {
-	views []View
-	size  int
-}
-
-// NewVectorisedView creates a new vectorised view from an already-allocated
-// slice of View and sets its size.
-func NewVectorisedView(size int, views []View) VectorisedView {
-	return VectorisedView{views: views, size: size}
-}
-
-// TrimFront removes the first "count" bytes of the vectorised view. It panics
-// if count > vv.Size().
-func (vv *VectorisedView) TrimFront(count int) {
-	for count > 0 && len(vv.views) > 0 {
-		if count < len(vv.views[0]) {
-			vv.size -= count
-			vv.views[0].TrimFront(count)
-			return
-		}
-		count -= len(vv.views[0])
-		vv.removeFirst()
-	}
-}
-
-// Read implements io.Reader.
-func (vv *VectorisedView) Read(b []byte) (copied int, err error) {
-	count := len(b)
-	for count > 0 && len(vv.views) > 0 {
-		if count < len(vv.views[0]) {
-			vv.size -= count
-			copy(b[copied:], vv.views[0][:count])
-			vv.views[0].TrimFront(count)
-			copied += count
-			return copied, nil
-		}
-		count -= len(vv.views[0])
-		copy(b[copied:], vv.views[0])
-		copied += len(vv.views[0])
-		vv.removeFirst()
-	}
-	if copied == 0 {
-		return 0, io.EOF
-	}
-	return copied, nil
-}
-
-// ReadToVV reads up to n bytes from vv to dstVV and removes them from vv. It
-// returns the number of bytes copied.
-func (vv *VectorisedView) ReadToVV(dstVV *VectorisedView, count int) (copied int) {
-	for count > 0 && len(vv.views) > 0 {
-		if count < len(vv.views[0]) {
-			vv.size -= count
-			dstVV.AppendView(vv.views[0][:count])
-			vv.views[0].TrimFront(count)
-			copied += count
-			return
-		}
-		count -= len(vv.views[0])
-		dstVV.AppendView(vv.views[0])
-		copied += len(vv.views[0])
-		vv.removeFirst()
-	}
-	return copied
-}
-
-// ReadTo reads up to count bytes from vv to dst. It also removes them from vv
-// unless peek is true.
-func (vv *VectorisedView) ReadTo(dst io.Writer, peek bool) (int, error) {
-	var err error
-	done := 0
-	for _, v := range vv.Views() {
-		var n int
-		n, err = dst.Write(v)
-		done += n
-		if err != nil {
-			break
-		}
-		if n != len(v) {
-			panic(fmt.Sprintf("io.Writer.Write succeeded with incomplete write: %d != %d", n, len(v)))
-		}
-	}
-	if !peek {
-		vv.TrimFront(done)
-	}
-	return done, err
-}
-
-// CapLength irreversibly reduces the length of the vectorised view.
-func (vv *VectorisedView) CapLength(length int) {
-	if length < 0 {
-		length = 0
-	}
-	if vv.size < length {
-		return
-	}
-	vv.size = length
-	for i := range vv.views {
-		v := &vv.views[i]
-		if len(*v) >= length {
-			if length == 0 {
-				vv.views = vv.views[:i]
-			} else {
-				v.CapLength(length)
-				vv.views = vv.views[:i+1]
-			}
-			return
-		}
-		length -= len(*v)
-	}
-}
-
-// Clone returns a clone of this VectorisedView.
-// If the buffer argument is large enough to contain all the Views of this
-// VectorisedView, the method will avoid allocations and use the buffer to
-// store the Views of the clone.
-func (vv VectorisedView) Clone(buffer []View) VectorisedView {
-	return VectorisedView{views: append(buffer[:0], vv.views...), size: vv.size}
-}
-
-// PullUp returns the first "count" bytes of the vectorised view. If those
-// bytes aren't already contiguous inside the vectorised view, PullUp will
-// reallocate as needed to make them contiguous. PullUp fails and returns false
-// when count > vv.Size().
-func (vv *VectorisedView) PullUp(count int) (View, bool) {
-	if len(vv.views) == 0 {
-		return nil, count == 0
-	}
-	if count <= len(vv.views[0]) {
-		return vv.views[0][:count], true
-	}
-	if count > vv.size {
-		return nil, false
-	}
-
-	newFirst := NewView(count)
-	i := 0
-	for offset := 0; offset < count; i++ {
-		copy(newFirst[offset:], vv.views[i])
-		if count-offset < len(vv.views[i]) {
-			vv.views[i].TrimFront(count - offset)
-			break
-		}
-		offset += len(vv.views[i])
-		vv.views[i] = nil
-	}
-	// We're guaranteed that i > 0, since count is too large for the first
-	// view.
-	vv.views[i-1] = newFirst
-	vv.views = vv.views[i-1:]
-	return newFirst, true
-}
-
-// Size returns the size in bytes of the entire content stored in the
-// vectorised view.
-func (vv *VectorisedView) Size() int {
-	return vv.size
-}
-
-// MemSize returns the estimation size of the vv in memory, including backing
-// buffer data.
-func (vv *VectorisedView) MemSize() int {
-	var size int
-	for _, v := range vv.views {
-		size += cap(v)
-	}
-	return size + cap(vv.views)*viewStructSize + vectorisedViewStructSize
-}
-
-// ToView returns a single view containing the content of the vectorised view.
-//
-// If the vectorised view contains a single view, that view will be returned
-// directly.
-func (vv *VectorisedView) ToView() View {
-	if len(vv.views) == 1 {
-		return vv.views[0]
-	}
-	return vv.ToOwnedView()
-}
-
-// ToOwnedView returns a single view containing the content of the vectorised
-// view that vv does not own.
-func (vv *VectorisedView) ToOwnedView() View {
-	u := make([]byte, 0, vv.size)
-	for _, v := range vv.views {
-		u = append(u, v...)
-	}
-	return u
-}
-
-// Views returns the slice containing the all views.
-func (vv *VectorisedView) Views() []View {
-	return vv.views
-}
-
-// Append appends the views in a vectorised view to this vectorised view.
-func (vv *VectorisedView) Append(vv2 VectorisedView) {
-	vv.views = append(vv.views, vv2.views...)
-	vv.size += vv2.size
-}
-
-// AppendView appends the given view into this vectorised view.
-func (vv *VectorisedView) AppendView(v View) {
-	if len(v) == 0 {
-		return
-	}
-	vv.views = append(vv.views, v)
-	vv.size += len(v)
-}
-
-// AppendViews appends views to vv.
-func (vv *VectorisedView) AppendViews(views []View) {
-	vv.views = append(vv.views, views...)
-	for _, v := range views {
-		vv.size += len(v)
-	}
-}
-
-// Readers returns a bytes.Reader for each of vv's views.
-func (vv *VectorisedView) Readers() []bytes.Reader {
-	readers := make([]bytes.Reader, 0, len(vv.views))
-	for _, v := range vv.views {
-		readers = append(readers, v.Reader())
-	}
-	return readers
-}
-
-// removeFirst panics when len(vv.views) < 1.
-func (vv *VectorisedView) removeFirst() {
-	vv.size -= len(vv.views[0])
-	vv.views[0] = nil
-	vv.views = vv.views[1:]
-}

pkg/tcpip/buffer/view_unsafe.go

@@ -1,22 +0,0 @@
-// Copyright 2021 The gVisor Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package buffer
-
-import "unsafe"
-
-const (
-	vectorisedViewStructSize = int(unsafe.Sizeof(VectorisedView{}))
-	viewStructSize           = int(unsafe.Sizeof(View{}))
-)

pkg/tcpip/checker/BUILD

@@ -8,8 +8,8 @@ go_library(
     srcs = ["checker.go"],
     visibility = ["//visibility:public"],
     deps = [
+        "//pkg/buffer",
         "//pkg/tcpip",
-        "//pkg/tcpip/buffer",
         "//pkg/tcpip/header",
         "//pkg/tcpip/seqnum",
         "@com_github_google_go_cmp//cmp:go_default_library",

pkg/tcpip/checker/checker.go

@@ -23,8 +23,8 @@ import (
 	"time"
 
 	"github.com/google/go-cmp/cmp"
+	"gvisor.dev/gvisor/pkg/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip"
-	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip/header"
 	"gvisor.dev/gvisor/pkg/tcpip/seqnum"
 )
@@ -1546,7 +1546,7 @@ func IPv6WithExtHdr(t *testing.T, b []byte, checkers ...NetworkChecker) {
 
 	payloadIterator := header.MakeIPv6PayloadIterator(
 		header.IPv6ExtensionHeaderIdentifier(ipv6.NextHeader()),
-		buffer.View(ipv6.Payload()).ToVectorisedView(),
+		buffer.NewWithData(ipv6.Payload()),
 	)
 
 	var rawPayloadHeader header.IPv6RawPayloadHeader
@@ -1570,7 +1570,7 @@ func IPv6WithExtHdr(t *testing.T, b []byte, checkers ...NetworkChecker) {
 	networkHeader := ipv6HeaderWithExtHdr{
 		IPv6:      ipv6,
 		transport: tcpip.TransportProtocolNumber(rawPayloadHeader.Identifier),
-		payload:   rawPayloadHeader.Buf.ToView(),
+		payload:   rawPayloadHeader.Buf.Flatten(),
 	}
 
 	for _, checker := range checkers {
@@ -1594,7 +1594,7 @@ func IPv6ExtHdr(headers ...IPv6ExtHdrChecker) NetworkChecker {
 
 		payloadIterator := header.MakeIPv6PayloadIterator(
 			header.IPv6ExtensionHeaderIdentifier(extHdrs.IPv6.NextHeader()),
-			buffer.View(extHdrs.IPv6.Payload()).ToVectorisedView(),
+			buffer.NewWithData(extHdrs.IPv6.Payload()),
 		)
 
 		for _, check := range headers {

pkg/tcpip/header/BUILD

@@ -32,7 +32,6 @@ go_library(
     deps = [
         "//pkg/buffer",
         "//pkg/tcpip",
-        "//pkg/tcpip/buffer",
         "//pkg/tcpip/seqnum",
         "@com_github_google_btree//:go_default_library",
     ],
@@ -51,9 +50,9 @@ go_test(
     ],
     deps = [
         ":header",
+        "//pkg/buffer",
         "//pkg/rand",
         "//pkg/tcpip",
-        "//pkg/tcpip/buffer",
         "//pkg/tcpip/prependable",
         "//pkg/tcpip/testutil",
         "@com_github_google_go_cmp//cmp:go_default_library",
@@ -71,8 +70,8 @@ go_test(
     ],
     library = ":header",
     deps = [
+        "//pkg/buffer",
         "//pkg/tcpip",
-        "//pkg/tcpip/buffer",
         "//pkg/tcpip/testutil",
         "@com_github_google_go_cmp//cmp:go_default_library",
     ],

pkg/tcpip/header/checksum.go

@@ -22,7 +22,6 @@ import (
 
 	"gvisor.dev/gvisor/pkg/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip"
-	tcpipbuffer "gvisor.dev/gvisor/pkg/tcpip/buffer"
 )
 
 // ChecksumSize is the size of a checksum.
@@ -193,18 +192,6 @@ func Checksum(buf []byte, initial uint16) uint16 {
 	return s
 }
 
-// ChecksumVV calculates the checksum (as defined in RFC 1071) of the bytes in
-// the given VectorizedView.
-//
-// The initial checksum must have been computed on an even number of bytes.
-func ChecksumVV(vv tcpipbuffer.VectorisedView, initial uint16) uint16 {
-	var c Checksumer
-	for _, v := range vv.Views() {
-		c.Add([]byte(v))
-	}
-	return ChecksumCombine(initial, c.Checksum())
-}
-
 // ChecksumBuffer calculates the checksum (as defined in RFC 1071) of the
 // bytes in the given Buffer.
 //

pkg/tcpip/header/checksum_test.go

@@ -23,8 +23,8 @@ import (
 	"sync"
 	"testing"
 
+	"gvisor.dev/gvisor/pkg/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip"
-	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip/header"
 )
 
@@ -63,8 +63,8 @@ func TestChecksumer(t *testing.T) {
 		{
 			name: "TwoEvenViews",
 			data: [][]byte{
-				buffer.NewViewFromBytes([]byte{98, 1, 9, 0}),
-				buffer.NewViewFromBytes([]byte{9, 0, 5, 4}),
+				[]byte{98, 1, 9, 0},
+				[]byte{9, 0, 5, 4},
 			},
 			want: 30981,
 		},
@@ -206,18 +206,16 @@ func TestICMPv4Checksum(t *testing.T) {
 	if _, err := rnd.Read(buf); err != nil {
 		t.Fatalf("rnd.Read failed: %v", err)
 	}
-	vv := buffer.NewVectorisedView(len(buf), []buffer.View{
-		buffer.NewViewFromBytes(buf[:5]),
-		buffer.NewViewFromBytes(buf[5:]),
-	})
+	b := buffer.NewWithData(buf[:5])
+	b.AppendOwned(buf[5:])
 
-	want := header.Checksum(vv.ToView(), 0)
+	want := header.Checksum(b.Flatten(), 0)
 	want = ^header.Checksum(h, want)
 	h.SetChecksum(want)
 
 	testICMPChecksum(t, h.Checksum, func() uint16 {
-		return header.ICMPv4Checksum(h, header.ChecksumVV(vv, 0))
-	}, want, fmt.Sprintf("header: {% x} data {% x}", h, vv.ToView()))
+		return header.ICMPv4Checksum(h, header.ChecksumBuffer(b, 0))
+	}, want, fmt.Sprintf("header: {% x} data {% x}", h, b.Flatten()))
 }
 
 func TestICMPv6Checksum(t *testing.T) {
@@ -233,17 +231,15 @@ func TestICMPv6Checksum(t *testing.T) {
 	if _, err := rnd.Read(buf); err != nil {
 		t.Fatalf("rnd.Read failed: %v", err)
 	}
-	vv := buffer.NewVectorisedView(len(buf), []buffer.View{
-		buffer.NewViewFromBytes(buf[:7]),
-		buffer.NewViewFromBytes(buf[7:10]),
-		buffer.NewViewFromBytes(buf[10:]),
-	})
+	b := buffer.NewWithData(buf[:7])
+	b.AppendOwned(buf[7:10])
+	b.AppendOwned(buf[10:])
 
 	dst := header.IPv6Loopback
 	src := header.IPv6Loopback
 
-	want := header.PseudoHeaderChecksum(header.ICMPv6ProtocolNumber, src, dst, uint16(len(h)+vv.Size()))
-	want = header.Checksum(vv.ToView(), want)
+	want := header.PseudoHeaderChecksum(header.ICMPv6ProtocolNumber, src, dst, uint16(len(h)+int(b.Size())))
+	want = header.Checksum(b.Flatten(), want)
 	want = ^header.Checksum(h, want)
 	h.SetChecksum(want)
 
@@ -252,10 +248,10 @@ func TestICMPv6Checksum(t *testing.T) {
 			Header:      h,
 			Src:         src,
 			Dst:         dst,
-			PayloadCsum: header.ChecksumVV(vv, 0),
-			PayloadLen:  vv.Size(),
+			PayloadCsum: header.ChecksumBuffer(b, 0),
+			PayloadLen:  int(b.Size()),
 		})
-	}, want, fmt.Sprintf("header: {% x} data {% x}", h, vv.ToView()))
+	}, want, fmt.Sprintf("header: {% x} data {% x}", h, b.Flatten()))
 }
 
 func randomAddress(size int) tcpip.Address {

pkg/tcpip/header/ipv6_extension_headers.go

@@ -23,8 +23,8 @@ import (
 	"io"
 	"math"
 
+	"gvisor.dev/gvisor/pkg/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip"
-	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 )
 
 // IPv6ExtensionHeaderIdentifier is an IPv6 extension header identifier.
@@ -161,7 +161,7 @@ type IPv6PayloadHeader interface {
 // header.
 type IPv6RawPayloadHeader struct {
 	Identifier IPv6ExtensionHeaderIdentifier
-	Buf        buffer.VectorisedView
+	Buf        buffer.Buffer
 }
 
 // isIPv6PayloadHeader implements IPv6PayloadHeader.isIPv6PayloadHeader.
@@ -469,7 +469,7 @@ type IPv6PayloadIterator struct {
 
 	// reader is an io.Reader over payload.
 	reader  bufio.Reader
-	payload buffer.VectorisedView
+	payload buffer.Buffer
 
 	// Indicates to the iterator that it should return the remaining payload as a
 	// raw payload on the next call to Next.
@@ -501,7 +501,7 @@ func (i IPv6PayloadIterator) ParseOffset() uint32 {
 
 // MakeIPv6PayloadIterator returns an iterator over the IPv6 payload containing
 // extension headers, or a raw payload if the payload cannot be parsed.
-func MakeIPv6PayloadIterator(nextHdrIdentifier IPv6ExtensionHeaderIdentifier, payload buffer.VectorisedView) IPv6PayloadIterator {
+func MakeIPv6PayloadIterator(nextHdrIdentifier IPv6ExtensionHeaderIdentifier, payload buffer.Buffer) IPv6PayloadIterator {
 	readers := payload.Readers()
 	readerPs := make([]io.Reader, 0, len(readers))
 	for i := range readers {
@@ -510,7 +510,7 @@ func MakeIPv6PayloadIterator(nextHdrIdentifier IPv6ExtensionHeaderIdentifier, pa
 
 	return IPv6PayloadIterator{
 		nextHdrIdentifier: nextHdrIdentifier,
-		payload:           payload.Clone(nil),
+		payload:           payload.Clone(),
 		// We need a buffer of size 1 for calls to bufio.Reader.ReadByte.
 		reader:     *bufio.NewReaderSize(io.MultiReader(readerPs...), 1),
 		nextOffset: IPv6FixedHeaderSize,
@@ -525,7 +525,7 @@ func MakeIPv6PayloadIterator(nextHdrIdentifier IPv6ExtensionHeaderIdentifier, pa
 func (i *IPv6PayloadIterator) AsRawHeader(consume bool) IPv6RawPayloadHeader {
 	identifier := i.nextHdrIdentifier
 
-	var buf buffer.VectorisedView
+	var buf buffer.Buffer
 	if consume {
 		// Since we consume the iterator, we return the payload as is.
 		buf = i.payload
@@ -537,7 +537,7 @@ func (i *IPv6PayloadIterator) AsRawHeader(consume bool) IPv6RawPayloadHeader {
 			nextOffset:        i.nextOffset,
 		}
 	} else {
-		buf = i.payload.Clone(nil)
+		buf = i.payload.Clone()
 	}
 
 	return IPv6RawPayloadHeader{Identifier: identifier, Buf: buf}
@@ -675,7 +675,7 @@ func (i *IPv6PayloadIterator) nextHeaderData(fragmentHdr bool, bytes []byte) (IP
 	}
 
 	n, err := io.ReadFull(&i.reader, bytes)
-	i.payload.TrimFront(n)
+	i.payload.TrimFront(int64(n))
 	if err != nil {
 		return 0, nil, fmt.Errorf("read %d out of %d extension header data bytes (length = %d) for header with id = %d: %w", n, bytesLen, length, i.nextHdrIdentifier, err)
 	}